Sports ball and method of manufacturing of same

ABSTRACT

A sports ball having an inflated or inflatable core (1), an outer covering (12, 13) enclosing the core (11), and a transparent cover layer (14) of transparent film applied to the outer surface of the core covering (12, 13), in which decorative markings (15) are provided at the interface between the internal face of the transparent cover (14) and the outer surface of the outer core covering (12, 13), preferably by application of the markings to the internal face of the transparent cover layer prior to lamination of the various layers of the core covering together. The outer covering on the core (11) may comprise more than one layer (12, 13), and may comprise conventional hand-sewn panels, or may comprise a covering of the non-hand-sewn type. The invention also relates to a method of manufacture of the sports ball.

This invention relates to a sports ball having an inflated or aninflatable core, and an outer covering enclosing the core.

Sports balls most commonly used at present fall into two maincategories: those having an external covering of hand-sewn components,foe example of synthetic material such as cloth or non-woven materialcoated with polyurethane by transfer; and those in which the covering isproduced not by a hand sewing operation but by the application of amoulded laminated structure which is generally achieved by mechanicalmeans.

In addition, the classical technique of ball manufacture consists inusing an internal bladder, usually of rubber. This is then coated with acloth component of natural or synthetic fibre or filament, these beingfor example wound progressively onto the bladder. To ensure theintegrity of the filament layer, it is combined with a composition,generally vulcanizable, most Often with a synthetic rubber base. Thefinal exterior covering is then applied on this composition.

It is usually desirable to provide decorative and/or informativemarkings on the outer covering, such as a supplier's logo. Usually thedecorative impressions for these two types of balls referred to above,(hand-sewn and non-hand-sewn), are applied onto the panels, [previouslycut out and ready to be assembled or laminated by gluing, in the flat]by silk screening, stamping, or more rarely thermal transfer. Theimpressions are applied to the outside face of the covering, so as to bedirectly visible on the finished ball.

The techniques just mentioned are well known in the trade y andtherefore do not need to be described in more detail. Whichever categorythey belong to, hand-sewn or non-hand-sewn, balls do not always givefull satisfaction to the makers of branded sports articles. These peopleare concerned about the life of the decorative impressions (a logoacting as the brand image of a company, or an imprint of a brand name orproduct name, or pictograms). They are also concerned about the life ofthe exterior covering, and about the regular sphericity of the ball whennew and its stability in use and over time.

To illustrate the unresolved problems for existing manufacture ofoutdoor and indoor sports at this time, it is sufficient to mention thefollowing:

The decorative impressions appearing on the balls are applied to theoutside of the exterior covering, and the known application techniquesmentioned above do not permit the application of films sufficientlythick to ensure a life longer than 20 or 25 hours of use. This is notmuch, considering that a competition ball in soccer, for example, has alife of more than 200 hours. The wear resistance and the adhesion aretherefore insufficient. Moreover, the fatty acids or plasticizers usedin preparing the pigment mixtures, and other thin layers on the surfacesuch as moisture from the atmosphere or dust, limit and irregularise theadhesion of the decorative printed film. These factors definitely reduceits life. This phenomenon can be clearly observed on a soccer ball, forexample, which has been used for fifteen hours or so; the decorativeimpressions are visible or invisible from one panel to another. Anothervery well known problem is that of the particularly poor resistance ofexterior decorative markings on balls used for indoor sports. Because ofthe friction caused by the contact of the balls with the surfaces foundin multi-sport indoor arenas, the film of marking ink tends to softendue to the heat generated, spread onto the unmarked white surfaces ofthe ball, and be transferred to the floors of the rooms, producingtraces which are difficult to clean. This makes maintenance of the roomslaborious.

Traditional coverings have a limited life as regards their resistance toscratching, Scuffing, cutting, or micro-perforation, and to abrasion,particularly by abrasive ground. These problems substantially impair theappearance of the ball, its watertightness on wet ground, and finallythe length of its life. The materials traditionally used as exteriorcoverings (cloth coated with PVC or polyurethane or various rubbermixtures) all comprise, without exception, a coating support, generallywith a synthetic or mixed or natural cloth base, or alternatively anon-woven base. The warp/weft extension of this material, i.e. itsextension equilibrium, is totally out of proportion, due to the tractionexerted on the warp in the coating process. This equilibrium cannot becontrolled or neutralized by the reinforcing cloths subsequently appliedby gluing and intended to stabilize the shape and circumference ofhand-sewn balls.

According to the invention there is provided a sports ball having aninflated or an inflatable core, and an outer covering enclosing saidcore, in which a transparent cover layer is applied to the outer surfaceof said outer covering, and markings are provided at the interfacebetween the internal face of the transparent cover layer and the outersurface of the outer covering, thereby to provide required externallyvisible markings of the sports ball.

Therefore, in a sports ball according to the invention, any requireddecorative markings e.g. manufacturer's name, logo or trade mark orother markings, are readily visible through the transparent cover layer,but are protected from wear and tear in service by being locatedadjacent to the internal face of the transparent cover layer.

Further, the underlying outer core covering is also readily visiblethrough the transparent cover layer, and may therefore be made of anydesired one of traditional designs or construction, or indeed otherdesigns and construction as required. The outer core covering thereforemay be made of hand-stitched panels, or other (non-hand-stitched) form.

The markings may be applied adjacent to the internal face of the coverlayer in any suitable manner, and are then shielded from any damage bybeing located adjacent to the outer surface of the core covering.

A sports ball according to the invention therefore overcomes thedrawbacks associated with existing manufacture of sports balls referredto above and permits the playing of sports and games with these balls,either indoors or outdoors, under conditions which satisfy both usersand the firms producing branded sports articles. The balls can retaintheir decorative markings throughout their working life i.e. until theother parts of the ball are no longer considered usable, and thereforerepresent a distinct improvement on the sports balls currentlyavailable.

Preferably, the markings are provided on the internal face of thetransparent cover layer, so as to lie adjacent to the outer surface ofthe outer covering on the core of the sports ball.

The transparent cover layer may be made from a thermoplastic polymerwhich is characterized by its transparency and the absence of a coatingsupport, and having extremely good physical and mechanical properties.Because of its transparency, the decorative markings can be applied tothe side facing inward, intended to be laminated with the sub-adjacentlayers, such as various foams and/or supports of whatever kind. Thedecorative markings are consequently visible, due to the transparency,on the surface of the ball and are completely protected against anyexternal agency or wear or premature degradation.

To the applicant's knowledge, the use of a transparent exteriorcovering, without a coating support and having decorative markingsfacing inward, has never before been proposed for sports balls.

The presence of an exterior layer of transparent material (preferably inthe form of a film without a coating support), confers on the internaldecorative markings and on the coating, and consequently on the ballitself, entirely advantageous properties and a surprising quality ofwear resistance.

In traditional balls the covering is pigmented, usually in white, and istherefore not transparent, and the decorative markings are applied tothe outside and on the surface. In contrast, the covering of a sportsball according to the invention is transparent, without coating support,and has good physical and mechanical properties. It allows thedecorative markings to be applied to the side of the covering film whichfaces inward, which is to be laminated with sub-adjacent layers whichmay be of conventional construction. The printed impressions are visibleon the finished ball through the transparent layer.

Because there is no coating support for the exterior covering, thesphericity can be perfectly controlled by applying reinforcing clothslaminated onto the face of the transparent exterior covering with thedecorative markings, in the case of hand-sewn balls.

The invention is applicable to all categories of balls and may be usedin hand-sewn or non-hand-sewn designs, except that in the case ofnon-hand-sewn balls, the sphericity is controlled by winding a filamenton as previously described.

In the case of a non-hand-sewn soccer ball, the internal core structureconsists of a bladder of natural or synthetic rubber, of butyl rubberfor example, with a winding of filament attached to a synthetic rubberbased composition (e.g. styrene butadiene rubber SBR). To this casingthe exterior covering layer is attached by full surface sticking ontothe rubber layer. Depending on the design, these layers will be attachedto an intermediate i.e. a sub-adjacent layer of a foam or non-wovenmaterial, for example. This is to make the structure flexible andfacilitate the operations of bevelling or trimming the edges forsticking or joining the panels and to obtain a good appearance.

In the case of a hand-sewn soccer ball, the internal core structureconsists of a bladder, of vulcanized natural latex for example. Thehand-sewn panels comprise, on the side facing inward, a cloth complexwhich may have several woven and/or non-woven components. Depending onthe design, the transparent exterior covering will be stuck directlyonto the cloth complex or attached to an additional subjacent layer, offoam for example, before being laminated to the cloth complex.

In the case of a rugby or handball ball, reference may be made to theforegoing, given that the basic construction of hand-sewn types issimilar.

Preferably, the transparent outer cover is formed by a transparent filmwithout coating support and with extremely good physical and mechanicalproperties, which produces very advantageous results.

A preferred example of transparent film for use as an exterior coveringwith no coating support, which has proved appropriate to therequirements of the invention, results from the chemistry ofpolyurethanes of the aromatic ether type and contains UV absorbentagents. By way of example, a transparent polyurethane film which hasgiven excellent results has a thickness of 500 microns and achieves aShore hardness of 85 points on scale A. Because of its composition andits physical properties as aforesaid, the following advantages areobtained in a sports ball:

resistance to cryptograms, hydrolytic deterioration, yellowing due toexposure to UV radiation, and accelerated ageing;

resistance to wear, scuffing, micro-perforation, and cutting; goodelastic memory, hence good acceleration of the ball when struck cleanly,no increase in hardness at low temperatures, hence the ball remainsflexible to touch and pleasant to the user in winter;

decorative markings can be applied to the side facing inward due to thetransparency of the exterior covering film, hence they last as long asthe ball itself;

better spherical conformation when new and better stability of shape inuse and over time, consequently more reliable trajectory and novibrations when the ball is flying at high speed, and regular, logical,and reliable behaviour in technical or critical phases of the game;

distinctly longer life, even on very abrasive terrain.

It should be understood that transparent films of different types ordifferent compositions may be used and that the thickness may be reducedto lower the cost of the finished product, but to the detriment of theproperties mentioned above. For example, a polyurethane film of theester type may be used as the exterior covering, although the resistanceto microorganisms, the stability to hydrolytic degradation, and theflexibility at low temperatures would be less good. The life of thefinished product would consequently be reduced.

The procedure for manufacturing a ball with a transparent exteriorcovering with decorative markings on the side facing inward, is slightlydifferent than for the manufacture of balls currently available on themarket. In existing manufacture, decorative printing is carried out onprecut (e.g. of hexagonal or pentagonal configuration), in the flat, bysilk screening; stamping, or more rarely thermal transfer. This is donejust before the manual cutting stage in the case of a hand-sewn ball,and just before the operations of full-surface sticking onto theframework of non-hand-sewn balls. The marking or printing is carried outwith inks based on polyurethane resins, PVC, or acrylic, depending onthe type of surface to be marked; or more rarely by means of film basedlabels, for example of polyurethane on siliconised paper, which can betransferred by the action of heat and pressure using relatively simpleelectro-pneumatic devices.

In the case of preferred examples of sports ball according to theinvention (with a transparent covering with no coating support), havingdecorative markings on the side facing inward, the marking operation iscarried out at a different stage in the construction of the balls. It iscarried out on the exterior covering alone, on a large surface, in theflat, with the contours of the cutting-out punch (so as to be able tocentre the punch relative to the decorative motifs when cutting out thepanels). This is done prior to lamination with the sub-adjacent layerssuch as foam or cloth complex. These layers facing the inside of theball are laminated or assembled on the face having the decorativemarkings, in the case of a hand-sewn ball. In the case of a ball of thenon-hand-sewn type, the transparent film used as exterior covering islaminated with a sub-adjacent layer, or not (depending on the design),after the operations of decorative marking; it is then cut out with apunch in the form of panels and stuck full surface onto the core coveredwith vulcanizable composition. In the case of non-hand-sewn balls, it isalso necessary to print the contours of the punches at the same time toallow the decoration to be centred on the panel.

The invention will be further illustrated, without being in any waylimited, by the following examples and description, referring to theappended drawings in which:

FIG. 1 represents a piece of transparent covering film to form atransparent outer cover of a sports ball according to the invention,having decorative markings applied flat and to a large surface, and atthe same time shows the contours of the hexagonal punches, whichfacilitate positioning the cutting tool and centring the decoration onthe underlying panels of the ball core;

FIG. 2 represents in cross section a piece of transparent covering filmfor balls, having decorative markings applied by silk screening, forexample, and on the side facing the interior of the ball;

FIG. 3 represents in cross section the outer shell structure of a sportsball according to the invention and in the form of a soccer, rugby, orhandball ball, incorporating decorative markings oriented toward theinterior of the ball and combined with the transparent exterior coveringwithout coating support; and,

FIG. 4 is a view, similar to FIG. 3 of a further embodiment of sportsball according to the invention.

In the following examples the transparent covering film used was apolyurethane film produced by blow moulding with close thicknesstolerance with an aromatic ether base, containing UV absorbents, andhaving a mean thickness of 500

Density of base polymer: 1.14 approx.

Shore A hardness: 85

Melting point (Koffler bench): 145°-55°" C.

Maximum thickness tolerance: ±10%

FIG. 1 represents a piece of transparent covering, prepared according tothe size of surface that it is desired to mark in a single operation anddesignated by the general reference 1. The decorative markings 3, andthe contours 2 of the cutting tool, for example hexagonal as shown inFIG. 1, are imprinted simultaneously on the whole of the surface of thecovering piece. This is a preferred means of applying markings to theinterface between the internal face of the transparent cover and theouter face of the covering (12, 13) on the core (11) of the sports ball.

FIG. 2 represents in cross section a piece of film or transparentcovering for balls, designated by the general reference 3. The reverseside of the transparent film 1 is turned inward and is to receive thesub-adjacent layers. This reverse side bears the decorative markings 2,applied by silk screening, for example, These markings will show throughthe transparent covering and be visible through the outer side 4, whichwill form the outside of the finished ball.

FIG. 3 represents in cross section the structure of a soccer, rugby, orhandball ball, designated by the general reference 10. The design ofthese balls is of the hand-sewn type. In their known form, these ballscomprise an inflatable bladder core 17, for example of vulcanized latex.To provide dimensional stability, the hand-sewn panels comprise, on theinside, a structure 12 of synthetic fibre cloth. In the example chosen,this structure 12 consists of three layers of cloth. The differentlayers are bound together by means of adhesive compositions based ondispersions in aqueous media. An exterior covering 14 is composed of atransparent film, on the reverse side of this, which is turned inwardand is in direct contact with the sub-adjacent layers, are decorativemarkings 15, applied before lamination with polyethylene foam 13 (ofclose cellular structure, cross linked by gamma irradiation) and thereinforcing cloth structure 12. The best results have been obtainedusing a film without coating support, transparent, composed ofthermoplastic polyurethane of the aromatic ether type, with elastomericbehaviour, a thickness of about 500 microns, Shore A hardness 85,produced by blow moulding and containing absorbents of ultravioletlight. Decorative markings of pleasing appearance and satisfactoryphysical and mechanical properties are generally obtained by the use oftwo-component polyurethane inks, for example.

FIG. 4 represents in cross section the structure of a soccer or handballball, designated by the general reference 20. The design of these ballsis of the non-hand-sewn type. In their known form, these balls comprisean inflatable bladder 27, of butyl rubber for example, mechanicallycovered by a multidirectional winding of filament 26, immersed andthereby stabilized in a vulcanizable composition 25. The exteriorcoating 21 is composed of a transparent film. On the side of this whichis turned inward and is in contact with the adjacent layers, are thedecorative markings 22 and a non-woven material 23 which serves toprovide volume and facilitate sticking to the vulcanizable composition25. Bevelling or trimming the edge 24 helps obtain a pleasing appearanceof the joints of the panels covering the entire surface of the ball.

It has been found that footballs, for example, which have a transparentexterior covering without a coating support, with decorative markingsfacing inward, achieve a distinctly longer product life with regard tothe surface covering and the permanence of decorative markings (whichmust always show up as clearly as possible in press photos or televisedpictures, however long the ball may have been in use). Further, suchballs behave in a reliable manner because of their better sphericalconformation and their stability of shape, even after very prolonged useand in the course of intensive training in shooting.

Balls produced in this way preserve their pleasing appearance over time,and their properties of watertightness on wet terrain or melting snow.They also maintain their sphericity, on which depends the high-speedflight trajectory and the reliable behaviour of the ball in highlytechnical or critical phases of the game.

In the foregoing examples of the invention the outer cover is formed bya thermoplastic polyurethane film with elastomeric properties, anaromatic ether base, and a thickness of 500 microns. This is produced byblow moulding and its hardness on the Shore A scale is 85 points. Ofcourse, comparable results can be obtained with materials of differenttypes and physical properties, produced by other processes such ascalendaring or transfer coating and having a different thickness (thismay be reduced to about 200 microns). The materials may be modified invarying degrees according to whether the balls are to be used indoors oroutdoors, the type of ball being designed, and the type of ground(grass, hard ground, packed earth).

We claim:
 1. A method of manufacture of a sports ball having aninflatable core comprising the steps of:a) providing a transparent coverlayer having an inward and outward side; b) applying decorative markingto said inward side of the transparent cover layer; c) laminatingsub-adjacent layers to said inward side; d) cutting the material with apunch to form panels; e) joining or assembling the panels together; andf) applying the assembled cover to said inflatable core with saidoutward side of said transparent cover layer outermost.
 2. A methodaccording to claim 1 in which said decorative markings are applied tosaid transparent cover layer with said transparent cover layer as a flatlayer.
 3. A method according to claim 2 in which said sub-adjacentlayers are laminated on to said transparent cover layer using adhesives.4. A method according to claim 1 in which said decorative markings areapplied by silk screen printing.
 5. A method according to claim 1 inwhich said transparent cover layer comprises a polyurethane filmproduced by blow molding.
 6. A method according to claim 1 in which saidtransparent cover layer is produced from polyurethane with an aromaticether base.
 7. A method according to claim 1 in which said transparentcover layer is produced for polyurethane with an ether base.
 8. A methodaccording to claim 2 in which said decorative markings are applied tosaid transparent cover layer along with contours, said contours definingthe boundary of the panels to be punched.
 9. A method according to claim3 in which said sub-adjacent layers comprise one or more fibre clothlayers and one or more foam layers laminated together.
 10. A methodaccording to claim 9 in which said sub-adjacent layer next to the saidtransparent cover layer is a polyethylene foam layer.
 11. A sports ballmanufactured according to the method of claim 1.